Updated: Jun 2, 2021
English Common Names: Kobus Magnolia, Northern Japanese Magnolia
Japanese Name (Katakana): コブシ
Japanese Name (Kanji): 辛夷
Height: 10 - 15 meters
Known as コブシ (Kobushi) in Japan, Magnolia kobus is native to Japan and Jeju Island of South Korea. In Japan, it appears in the wild in Hokkaido, Honshu, Kyushu, and Shikoku, but is more commonly seen in eastern Japan. Often, they grow on mountains, hills, shrub-lands, and in secondary forests, which are forests that have naturally regenerated after significant disturbance or destruction to the original or primary forest.
Magnolia kobus is notable in Japan for the timing of its blooms. Known as one of the first magnolia species to bloom in the spring (blooming even before Somei-Yoshino cherry trees), it is one of the markers of spring in Japan. As a result, the flowers of Magnolia kobus have historically been important to Japanese farmers, indicating the beginning of the planting season. An alternative name for this species is Tauchi-zakura (田打ち桜) which literally means “rice-planting cherry blossom.”
Perhaps because of its important link to Japanese agriculture, Magnolia kobus is also associated with a number of historical popular and folk beliefs. Many of these folk beliefs were compiled and published in Nihon Zokushin Jiten (Dictionary of Japanese Popular Beliefs) in 1982 by Tozo Suzuki, a professor of Japanese literature and language that specialized in oral traditions. The book compiles the popular beliefs surrounding specific species that have been passed down in various regions in Japan. Among those, the beliefs and traditions for Magnolia kobus include:
Harvest and Climate Predictions
Given the early timing of its blooms, there are many agricultural beliefs and practices surrounding the flowers of Magnolia kobus. In some places in Yamagata, Miyagi, and Fukushima prefectures, the bloom of Kobushi flowers served as a cue to start building a rice nursery. In Nagano, it was an indicator of when to start sowing potatoes, and in Niigata, it was a sign to sow soybeans and harvest the fiddleheads of ferns like Osmunda japonica, which can be eaten as vegetables.
Aside from the timing of Magnolia kobus blooms, the amount of flowers produced in a given spring were also sometimes thought to be indicative of the success of the following harvest season. In Akita, Yamagata, Miyagi, Fukushima, Gunma, Niigata, Gifu, Nagano, Fukui, Shiga, Kyoto, and Hiroshima prefectures, a year with a lot of Kobushi flowers were thought to indicate a good harvest year. In Niigata, the presence of many Kobushi flowers in spring pointed to a good sardine harvest year. However, not all prefectures associated lots of Kobushi flowers with bountiful harvest. A plethora of Magnolia kobus flowers in the Senboku region of Akita prefecture was thought to indicate that a bad rice harvest year was in store.
Alongside predicting the success of the harvest, Kobushi flowers were also looked at to predict the climate in some parts of Japan. For example, in some regions of Akita, Yamagata, and Miyagi prefectures:
If the flowers bloom facing upwards, there will be a drought.
If they bloom facing downwards, there will be a lot of rain.
If they bloom facing sideways, there will be a lot of wind.
Among the variety of medicinal uses listed for Kobushi, some include:
Kobushi bud infused tea which was used for headache relief, swollen skin, and stomach-related symptoms (Iwate and Yamagata prefectures)
Dried Kobushi flowers mixed with licorice for mental illnesses (Gifu prefecture)
Preparations of Kobushi seeds for reproductive diseases (Shiga prefecture)
Preparations of Kobushi flowers for gynecological diseases (Sannohe region, Aomori prefecture)
A special thank you to Keita Watanabe for providing access to a copy of Nihon Zokushin Jiten.
Leaves: Leaves are simple, deciduous, have smooth edges, alternate along the stem, and are 6 - 15 long and 3 - 16 cm wide. They produce a very fragrant magnolia smell if torn or crushed. If bitten into, they have a spicy taste similar to the paralyzing spicy feel of Chinese pepper (rather than the hot spiciness of a red pepper). Leaves turn yellow-brown in the fall.
Bark and Wood: The bark is thin, smooth, and easily breakable. It is most often gray or silver in color. Its wood has been used for utensils, crafts, and construction.
Flowers and Fruit: Flower buds are covered in small silver hairs. Flowers appear March - April and are among the earliest magnolia species to bloom in spring and bloom before leaves appear on the tree. The flowers are white (with sometimes pinkish-purple edges) with 6-9 tepals (a term that includes petals and sepals, often when the two can’t easily be differentiated). The flowers are slightly aromatic and about 10 cm across. Flowers are perfect (or hermaphroditic), having both male and female parts in each flower and do not produce nectar. Pollen-eating beetles often pollinate these flowers. Some trees may take up to 30 years to reach full flowering potential.
Fruits are in the shape of bulbous, conjoined seed pods up to 8 cm long. When ripe, the fruit is reddish-pink and splits open, which attracts many birds.
Breen, Patrick. “Magnolia Kobus.” Landscape Plants , Oregon State University, Department of Horticulture, 2020, landscapeplants.oregonstate.edu/plants/magnolia-kobus.
Hinchcliff, Richard, and R. V. Popadiouk. For the Love of Trees: a Guide to the Trees of Ottawa's Central Experimental Farm Arboretum. General Store Pub. House, 2007.
“Japanese Magnolia .” The Morton Arboretum , www.mortonarb.org/trees-plants/tree-plant-descriptions/japanese-magnolia.
Kwon, Ohjung, et al. "Emergence and settlement of Magnolia kobus in urban forests of Seoul, Korea." Forest Science and Technology 15.2 (2019): 63-69.
“Magnolia Kobus.” Plant Finder, Missouri Botanical Garden, www.missouribotanicalgarden.org/PlantFinder/PlantFinderDetails.aspx?taxonid=282534.
Suzuki, T. (1982). Nihon Zokushin Jiten (Animals and Plants Edition). Tokyo, Japan: Kadokawa Shoten. (Copy provided courtesy of Keita Watanabe)
Field Guides Consulted:
Title: 葉っぱで見分け五感で楽しむ樹木図鑑 (Happa de miwake gokan de tanoshimu jumokuzukan)
Author: 林将之 (Hayashi Masayuki)
Publishing Date and Publisher: 2014, ナツメ社
Title: 樹皮・葉でわかる樹木図鑑 (Juhi・Hadewakaru jumokuzukan)
Author: 菱山忠三郎 (Hishiyama Chuzaburo)
Publishing Date and Publisher: 2011, 成美堂出版
Photos by Taiga Araki and Siri McGuire